AHA: Caffeine Has Mixed Effects on Heart Health
Higher intake is linked to reduced risk of arrhythmia hospitalization and diabetes
WEDNESDAY, March 3 (HealthDay News) -- Caffeine consumption is associated with several positive or benign effects on cardiovascular health, but low-to-moderate consumption may be associated with a slightly elevated risk of hypertension, according to a series of studies presented this week at the American Heart Association's joint conference of the Council on Epidemiology and Prevention and the Council on Nutrition, Physical Activity and Metabolism, held from March 2 to 5 in San Francisco.
In one study, Arthur L. Klatsky, M.D., of the Kaiser Permanente Medical Care Program in Oakland, Calif., and colleagues assessed 130,054 members of a prepaid health care plan, including 3,137 who subsequently had a primary discharge diagnosis of cardiac dysrhythmias. Compared to patients in the lowest quartile of caffeine intake, they found that those in the highest quartile of caffeine intake had a significantly decreased risk of hospitalization for arrhythmias. In a second study, Jared P. Reis, M.D., of the Johns Hopkins Bloomberg School of Public Health in Baltimore, and colleagues assessed 5,115 subjects, and after a 20-year follow-up, they found that coffee consumption did not increase or decrease odds for prevalent or incident coronary artery calcification or high carotid intima-media wall thickness.
In a third study, researchers from the University of California in Los Angeles conducted a nested case-control study in the Women's Health Study and found an inverse relationship between coffee consumption and type 2 diabetes mellitus due mostly to effects of caffeine on sex hormone-binding globulin metabolism. A fourth study, a meta-analysis of six studies involving 172,567 participants, suggested that habitual low-to-moderate coffee consumption (one to three cups per day) may be associated with a slightly increased risk of hypertension.
"Findings from this meta-analysis of long-term cohort studies suggest that individuals with habitual low-to-moderate coffee consumption (one to three cups/day) may have [a] slightly elevated risk of hypertension. However, the number of studies is small and it is uncertain whether this relationship is independent of known dietary risk factors for hypertension," the authors of the fourth study write.